Well-drilling apparatus



Patented May 4, "1926.

UNITED STATES Isaac H. REAVIS, or swnn'r SPRINGS, mrssormr'.

WELL-DRILLING APPARATUS, I

I Application filed June 19, 1925. Serial No. 38,335.

To all whom it may concern:

Be it known that I, ISAAC H. REAVIS, a

i citizen of the United States, residing at Sweet Springs, in the county of Saline and State of Missouri, have invented new and useful Improvements in VVell-Dnlling Apparatus, of which the tollowingis a specification.

This invention relates generally to well drilling apparatusand has particular relation to means for breaking the joint to disconnect a drill bit jfrom the pipe or string, the invention being capable of use either with a rotary or fish tail bit.

Another object of the invention is the provision of a device of this character which combines with the above and other advantageous features, means to prevent the bit or other element from falling into the well hole.

With the above and other objects in view, the invention further includes the following novel features and details of construction, to be hereinafter more fully described, illustrated in the accompanylng drawings and pointed out in the appended claims.

In the drawings Figure 1 is a view partly in section and partly in elevation illustrating the use of the invention.

Figure 2 is a plan view of the device per 'se with its sections shown separated.

Figure 3 is a sectional view on the line 33 of Figure 2.

Figure 1- is a fragmentary plan view of the turn table.

Figure 5 is a transverse sectional view of a rotary bit.

Referring to the drawings in detail wherein like characters of referencedenote corresponding parts, the reference character 10 indicates a portion of the turntable of an ordinary rotary drilling apparatus for use in boring wells. This turntable is provided with a circular opening 11 and a rectangular socket 12, the opening being for the passage of the drilling tools while the socket receives the rectangular flange provided at one end of the ordinary spider used for connecting the turntable with the string.

Considerable difliculty is experienced in breaking the joint between the lowermost pipe section of. the string and the drill bit, the string being pulled so as to remove the bit from the hole. During the drilling operation, the. joint mentioned becomes tightly set and the bit and string must 'be securely engaged to unscrew the connection, considerable force being-required for this purpose. Frequently, during this operation of breaking the joint, the drill bit which is.

of considerable weight, falls downward into the hole so that it must be fished out.

The present invention 'aims to overcome these and other disadvantages by providing means for closing the opening during the removal of the drill bit and combining with this opening closing means, means to hold the drill bit against rotation so as to aid n breaking the joint. Forthis purpose, the invention provides a cylindricalmember or spider which is formed of two complemental sections 13. Each of these sections consists of a substantially semi-circular memher which is curved at one end so that these members 13 will, when placed together, form acyllnder or pocket which is closed at one end as shown at 14. The opposite end of the members 13 carry rectangular flanges 15 which form a square flange adapted to be seated within and engage the walls of the socket 12 of the turntable 10. The cylindrical member or pocket will thus close the opening 11 at the upper end of the well hole and will be held rigid with respect to the turntable. The members 13 are provided with handles-or bails 16 to facilitate their insertion and removal.

In the use of the invention as thus far described, when the string is pulled, the sections 13 of the pocket are placed within the opening 11 and the drill bit which is indicated at 17 is lowered within this pocket so as to bring the joint into convenient position. After the bit has been disconnected from the string it will be held within the pocket and thus prevented from falling into the hole.

Formed in the walls of the pocket at diametrically opposite points are recesses 18 which provide spaced shoulders 19 and these recesses are adapted to receive the usual lateral extensions 19 carried by the bit 17, the opposite side edges of these extensions engagingl the shoulders 19 so that the bit will be eld against rotation. In addition, the pocket has extending from diametrically opposite sides thereof, lugs 20 which are adapted to be received within the angular portion 21, of the bit and provide a support for the latter so as to prevent the cutting elements 22 of the bit from contacting the closed end of the pocket.

While the invention is shown and described in connection with a rotary bit, it may also be used with an ordinary fish tail bit, the side edges of a bit of this latter type engaging the lugs 20 so that the bit will be held against rotation when being disconnected from the string.

The invention is susceptible of various changes in its form, proportions and minor details of construction and the right is herein reserved to make such changes as properly fall within the scope of the appended claims.

Having described the invention what is claimed is 1. In a well drilling apparatus, the combination with a turntable, of means removably positioned within the opening of the turntable to close said opening and receive a drill bit.

2. In a well drilling apparatus, the combination with a turntable. of means removably positioned within the opening of the turntable and held against relative movement to close said opening and means included in the closing means to engage the bit and hold the latter against rotation.

3. In a well drilling apparatus, the combination with a turntable, of a substantially cylindrical member closed at one end and adapted-to be positioned within the opening of the turntable, means to hold the cylindrical member and turntable against relative rotary movement and means included in the walls of the cylindrical member for detachable engagement with a drill bit to hold the latter against rotation.

4. In a well drilling apparatus, the combination with a turntable, of a substantially cylindrical member closed at one end and adapted to be positioned within the opening of the turntable. means to hold the cylindrical member and turntable against relative rotary movement and diametrically located stops provided within the cylindrical member for engagement with the drill bit to hold the latter against rotation. 5. In a well drilling apparatus, the combination with a turntable, of a pair of complemental members, each of said members comprising a hollow substantially semi-circular portion and a flange at one end of said portion, said members being adapted to be associated to provide a pocket closed at one end and provided at its opposite end with a rectangular flange to engage the walls of the turntable socket, spaced stops provided within the pocket to engagea drill bit and prevent rotation of the latter and means within. the pocket to engage andsupport the bit.

In testimony whereof I aflix my signature.

ISAAC H. REAvIs. 

